Rafael Nadal and David Ferrer have dominated their preliminary matches at the 2014 French Open. Now it's time for the quarterfinals where most of the strongest players in tennis are still competing. This is where the road to the title actually begins.

In the past, Nadal would have been a heavy favorite to step over Ferrer on his way to another Musketeers' Cup. This was the final result to the 2013 French Open final when Nadal picked up his record-extending eighth title at Roland Garros.

But there is a different flavor to this quarterfinal. Ferrer defeated Nadal at Monte Carlo last month, and Nadal has struggled to find his most dominant form in 2014. Now comes the real test for both players.

Who Has the Historical Edge?

Christophe Ena/Associated Press

World No. 1 Rafael Nadal is Spain's golden success. It's not just that he has overshadowed compatriot David Ferrer, but it's a lesson in the difference between being a legend and being very good. Sometimes they play tight matches and it would not appear that their career results could be so lopsided, but tennis is a sport where only the absolute best get all the spoils.

Ferrer has 1 major runner-up, 1 Masters 1000 title and 11 clay titles.

Their career head-to-head record shows Nadal winning 21 of 27, including the 2013 French Open final. Ferrer won their first meeting on clay in 2004, but Nadal won 17 consecutive matches on this surface. The streak finally ended at Monte Carlo last month as Ferrer pulled out a straight-sets victory to advance to the quarterfinals.

Ferrer's Monte Carlo victory gives him an opening for Wednesday's clash, although Ferrer admitted In ATP World Tour that he will need some help to get it done:

I hope that I will instill some doubts in Rafa's mind, but if we play at our best level, both of us, he will be the better player. So I will pull out all the stops to play well without making errors, and we'll see what's going to happen.

Ferrer at the French Open

Michel Euler/Associated Press

David Ferrer is the hallmark of consistency. He almost always defeats the players that are ranked below him, and he plays even harder against the best players. His heart can never be questioned, even if he does not possess the weapons of his more famous rival and top contemporaries.

So it's hardly surprising that Ferrer has cruised through an easy draw in winning his four matches against Igor Sijsling, Simone Bolelli, Andreas Seppi and Kevin Anderson. He has dominated 11 of the 13 sets he has played, splitting two tiebreakers (winning the middle-set tiebreaker against Seppi in the third round; losing the third-set tiebreaker against Anderson in the fourth round).

The victory over big-serving Anderson is an example of Ferrer's resilience and all-around game. He is still one of the top retrievers in tennis, and over the course of several sets will figure out how to utilize his strong return game. He moved Anderson around and his energy was much higher by the fourth and final set.

Ferrer is the Energizer Bunny with his conditioning and spirit. He will be well rested and ready for his showdown against Nadal.

Nadal at the French Open

Michel Spingler/Associated Press

Nadal's draw quarter was lined up with dangerous players including young Dominic Thiem, Grigor Dimitrov, Nicolas Almagro and David Ferrer. SI.com's post-draw analysis listed it as the toughest potential road of the top players.

Of course draws never work out the way they are projected. Only Ferrer remains as scheduled, and potential semifinal opponent and World No. 3 Stanislas Wawrinka has long since departed. Nadal thrashed all four of his opponents (Robby Ginepri, Thiem, Leonardo Mayer and Dusan Lajovic) in straight sets, winning 73 of the 96 games.

It's a relief to Nadal for several reasons. Prior to Paris, he came off his poorest showing of the clay-court season, and there were questions about his game and confidence. Courtney Nguyen of SI.com gave her pre-tournament assessment:

So we head to Paris with some questions about Rafael Nadal, whose sole European clay title came via retirement at the Madrid Open. He’s been thoroughly outplayed by Djokovic twice this season...It’s clear that Nadal is having issues with his serve. He’s struggled to serve out sets and matches this week, and he was broken at a more frequent rate than ever in a best-of-three tournament. Mentally he’s still struggling to assert himself when he gets backed in a corner. Can he fix it all in a week?

The best news for Nadal is that he conserved more energy for the grueling stretch he could face ahead. There are three possible matches ahead and days off between matches. He should feel more confident and be able to draw on his past success at Roland Garros.

A footnote to Nadal's success: He has now won 32 straight matches at Roland Garros, which exceeds the 31 consecutive wins he had amassed before his 2009 fourth-round defeat to Robin Soderling.

The Biggest X-Factors

Michel Spingler/Associated Press

Nadal's Back: It would be the exception if Nadal were completely healthy. In Australia, he dealt with a massive blister on his hand, but he was ultimately undone by a back injury that cost him a chance to compete at his best in the final loss to Stanislas Wawrinka. Nadal's knee injuries have had countless reports and updates for the duration of his career. Fortunately, other than fatigue, he seems fine here.

But Nadal's back has been a problem. His serving speeds dropped in each of his first three matches, according to The Telegraph. It reports that his serving in the Ginepri match had him average 179 kph and 140 kph for first and second serves respectively. In his third match against Mayer, Nadal's serving dropped to 165 kph and 131 kph.

Nadal admitted that the back is indeed troubling him, as noted in the previous source:

I felt my back a little bit, so that’s why I slowed down the serve a little bit. I felt it a little bit from the beginning [of the tournament]. In the second match I was not serving that fast, too. I had the problem in Australia. It’s real.

Nadal's serving speed did pick up again in the fourth round, but it could be the most important x-factor for how he performs in the quarterfinals.

Ferrer's Belief: Ferrer has often looked overwhelmed playing Nadal. Despite his hustle and energy, there's simply not much he can do when Nadal is on his game. But he has defeated Nadal in two of the last three meetings and said in ATP World Tour that he is more composed:

I was very nervous [last year in the final]. I was jittery. It was a little bit too much for me. But now I'm calmer, I've had time to adapt. I think that I will be calmer, more serene, but I don't know exactly what will be my state of mind when I play against Rafa. I won't think about the final that took place last year.

A fast start for Ferrer could be the answer to even greater belief, especially if a longer match wears on Nadal's back and body. It used to be a certainty that Nadal was a slam dunk in five-set matches, but Ferrer's belief in a possible fifth set could make that scenario a coin toss.

David Ferrer Will Win the Quarterfinal If...

Michel Euler/Associated Press

Nadal can be a slow starter, feeling his way into matches. Ferrer needs to burst out with accurate and penetrating groundstrokes, letting his bigger rival know that the match will be a barn burner. If he wins the first set, call in for lunch, because it might be a four-hour affair.

Ferrer defeated Nadal at Monte Carlo for a few key reasons, which you can review here:

He attacked Nadal's backhand 79 percent of the time in the first set, coercing several short balls that Ferrer put away.

He adapted a piece of the Djokovic game plan, to use angles towards Nadal's ad corner. It forced Nadal to scramble more defensively and took away his control and powerful forehand offense.

He matched Nadal's winners (24 apiece) but was much cleaner than Nadal with only 28 unforced errors compared to Nadal's 44 errors.

Ferrer must also return well and take advantage of break-point opportunities. Last year's French Open final saw him convert only three of 12 chances while Nadal cashed in on eight of 16 opportunities. If Nadal's serving speed is below par, expect Ferrer to lock in and control the pace.

Finally, if Ferrer can play clean tennis, he might be able to force Nadal into more errors. Running around and winning most of the extended rallies (above 10 strokes) can be a psychological boost. Later in his career, Nadal has transitioned to try and attack more early in the points. Ferrer will need to often get these attacks back to neutral and force the King of Clay into a long day.

I will try to do my best. I will try to play aggressively with my forehand and try to finish the points at the net. But of course it's going to be difficult with Rafael on a clay court. Tactically, I will have to be perfect.

All of this will need to pay off for Ferrer, but he must also face a lackluster Nadal. He does not possess the power to overwhelm Nadal, so he needs Nadal's errors and poor strokes to set up his own finishes.

Rafael Nadal Will Win the Quarterfinal If...

Darko Vojinovic/Associated Press

Strangely, we know more about what we will get from Ferrer than Nadal. If Nadal had been ripping through the past six weeks in top form, there would be no need to analyze this match. He has pushed aside a weak lineup so far, but this match will give us a better sense of what to expect going forward.

Is Nadal near the form that has won eight of the past nine French Open titles, or will he struggle with more of his recent vulnerabilities?

If Nadal is serving with strong variety and effectiveness, he will be able to set up his forehand and dictate play. He wants to lock in with his offense, penetrate deep and flat with his backhand, crush his inverse forehand and pull a heavy dose of topspin to Ferrer's backhand.

The Nadal forehand has always been the biggest difference between these two. Last year's French Open final produced 19 forehand winners from Nadal but only 10 for Ferrer. Their seven backhand winners were a stalemate and their unforced errors (45-42 Nadal) were nearly even. Nadal's big hammer is the key.

Nadal's tendencies are to start conservative and play to his margin of safety. He will force Ferrer to go for his shots, but if both players are locked in, Nadal is a bigger finisher. Add into this his history of domination over Ferrer and Roland Garros, Nadal's A-game will win handily and even his B-game would probably be enough.

Watch to see how far back Nadal decides to play Ferrer's second serves. If he gives up too much ground, Ferrer could get enough short balls to create pressure.

Nadal also needs to come in behind some of his big approach shots. He is an underrated net player and one of the best ever at finishing overhead smashes. These easier points also give him that extra sense of confidence that can quickly roll over his opponents.

Optimum health, sharp execution and big-match energy are the driving force to another Nadal victory.

Prediction

Michel Spingler/Associated Press

Ferrer has Nadal's attention; he will not sneak up on his bigger rival, especially because Nadal is probably still smarting from the Monte Carlo match. He may not talk about revenge, but his respect and preparation for Ferrer are evident, as he explained in ATP World Tour:

I think that I am playing a little bit better than when I was playing against him in Monte-Carlo, but I think he's playing great, too. He played three weeks in a row at a very high level. In Madrid he played great, in Rome he played great, and he's playing great here.

He's coming to the match with confidence and with confidence that he beat me the last time. It will be a tough one. I know how to play against him and to have chances to win I need to play very well. That's what I'm going to try. If not, it will be impossible.

Nice words, but Nadal is still the king of clay until further notice. Whatever his maladies, Roland Garros has been the healing balm. He should be rested and ready to play Nadal tennis, and if so, he could sweep Ferrer.

But Ferrer is a fighter. We will give him one set, which is a great effort, but not enough to defeat Nadal at his most treasured battle arena.

Nadal will move on to another very interesting semifinal match featuring tough Andy Murray or flamboyant French hero Gael Monfils.